Company lists · Data refreshed September 2026

Top 25 Epa consulting firms based in Washington, United States

RevenueBase identified 59 epa consulting firms headquartered in Washington, United States as of September 2026 and tracks 466 professional contacts across them, including 245 with verified work emails. Across the United States, Houston is the largest hub for this category (90 companies); Washington has 59.

This list covers epa consulting firms headquartered in Washington, United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 28, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 28, 2026 86% judged on-target in blind review
59Companies
466Contacts tracked
245Verified emails
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The 25 largest epa consulting firms based in Washington, United States

Ranked by team size
Top 25 of 59 epa consulting firms based in Washington, United States, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to epa consulting firms: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202651-20071 contacts →

Indirect evidence

“In 1978, PEER was established under Dr.”

Source: RevenueBase Database · checked Sep 28, 2026
2Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 202651-20063 contacts →

Partial evidence

“Baumann Consulting is driven to deliver solutions for a carbon-neutral real estate industry.”

Source: RevenueBase Database · checked Sep 28, 2026
3Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5032 contacts →

Partial evidence

“The Environmental Protection Network harnesses the expertise of over 750 former EPA career staff and political appointees from across the country to serve as a trusted resource…”

Source: RevenueBase Database · checked Sep 28, 2026
4Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202651-20030 contacts →

Indirect evidence

“SaLUT is a client-focused company.”

Source: RevenueBase Database · checked Sep 28, 2026
5Indirect evidenceWashington, United StatesHQ checked Sep 28, 202611-5024 contacts →

Indirect evidence

“At Northbridge, we provide our clients with the tools and expertise to help solve complex financial, policy, and environmental challenges.”

Source: RevenueBase Database · checked Sep 28, 2026
6Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5019 contacts →

Partial evidence

“The Clark Group is an environmental policy consulting firm that provides a broad range of services to government, private and nonprofit clients.”

Source: RevenueBase Database · checked Sep 28, 2026
7Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5018 contacts →

Indirect evidence

“At Earth & Water, we are more than lawyers – we’re strategic advisors with unique experience who advance our clients’ interests across a broad range of environmental and business…”

Source: RevenueBase Database · checked Sep 28, 2026
8Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5016 contacts →

Indirect evidence

“Dawson & Associates is the nation’s premier firm for resolving complex challenges involving Federal water and environmental policies.”

Source: RevenueBase Database · checked Sep 28, 2026
9Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5015 contacts →

Indirect evidence

Source: RevenueBase Database · checked Sep 28, 2026
10Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5014 contacts →

Partial evidence

“ToxServices is a scientific consulting firm providing with more than a decade of expertise in toxicology, risk assessment, comparative hazard assessment, and the application of…”

Source: RevenueBase Database · checked Sep 28, 2026
11Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-1014 contacts →

Indirect evidence

“CO2EFFICIENT LLC (COEFFICIENT) was founded in 2017 as a mission-focused Washington, D.C.”

Source: RevenueBase Database · checked Sep 28, 2026
12Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-1014 contacts →

Partial evidence

“Blackwoods Group is an agriculture and natural resource consulting firm that provides a variety of services ranging from government relations to development and implementation of…”

Source: RevenueBase Database · checked Sep 28, 2026
13Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-1011 contacts →

Partial evidence

“Sustainable Strategies DC is a government affairs and strategic consulting firm based in Washington, DC, that helps clients secure resources for community revitalization and tools…”

Source: RevenueBase Database · checked Sep 28, 2026
14Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202651-20011 contacts →

Indirect evidence

“For over 30 years, TSG has provided companies around the world with regulatory guidance and scientific expertise.”

Source: RevenueBase Database · checked Sep 28, 2026
15Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-5010 contacts →

Indirect evidence

“The Wright Way Enterprises (TWW) is certified as an SBA 8(a) and HUBZone small business and DC Certified Business Enterprise (CBE), stewarding organizations in addressing the…”

Source: RevenueBase Database · checked Sep 28, 2026
16Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-108 contacts →

Indirect evidence

“Green Strategies Inc.”

Source: RevenueBase Database · checked Sep 28, 2026
17Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-107 contacts →

Partial evidence

“DRM International, Inc,(DRM) is a leading DIsadvantaged Business Enterprise (DBE) professional engineering consulting firm offering engineering, architectural, planning…”

Source: RevenueBase Database · checked Sep 28, 2026
18Indirect evidenceWashington, United StatesHQ checked Sep 28, 20261-107 contacts →

Indirect evidence

“Green Capitol LLC works on sustainable development policy at the state, federal and international levels, serving clients on agriculture, energy and environment concerns via…”

Source: RevenueBase Database · checked Sep 28, 2026
19Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-106 contacts →

Partial evidence

“Energy Shrink is an environmental consulting practice specialized in sustainability and energy efficiency in buildings, that is, high-performance or green buildings.”

Source: RevenueBase Database · checked Sep 28, 2026
20Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 202611-505 contacts →

Partial evidence

“For over 30 years, Washington Occupational Health Associates (WOHA) has been the leading provider of expert occupational, environmental, and public health consulting services to…”

Source: RevenueBase Database · checked Sep 28, 2026
21Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-104 contacts →

Indirect evidence

“Leading and innovative company that finding solutions, bridging gaps and driving positive action for clients and the planet.”

Source: RevenueBase Database · checked Sep 28, 2026
22Indirect evidenceWashington, United StatesHQ checked Sep 28, 20261-104 contacts →

Indirect evidence

“Sustainability Frameworks helps its public and private sector clients develop strategies to manage their environmental and social risks and opportunities, optimize their…”

Source: RevenueBase Database · checked Sep 28, 2026
23Indirect evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-104 contacts →

Indirect evidence

“JG Global Advisory, LLC is a minority, woman-owned small business (WOSB) consultancy providing advisory services and integrated solutions for environmental and international…”

Source: RevenueBase Database · checked Sep 28, 2026
24Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-103 contacts →

Partial evidence

“Strategic Conservation Solutions, LLC (SCS) is a specialized consulting firm providing advocacy, visioning and strategic positioning to firms and associations in the areas of…”

Source: RevenueBase Database · checked Sep 28, 2026
25Partial evidenceWashington, DC, United StatesHQ checked Sep 28, 20261-103 contacts →

Partial evidence

“Warwick Group Consultants is the Nation's premier consulting firm for local governments with coastal projects involving beach nourishment, dredging, aquatic ecosystem restoration…”

Source: RevenueBase Database · checked Sep 28, 2026

Showing 25 of 59 epa consulting firms based in Washington, United States

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Epa consulting firms based in Washington, United States at a glance

As of Sep 28, 2026
52.6%Verified-email coverage
7.9Average contacts per company
1-10Median size (employees)
Sep 28, 2026Page data refreshed

Companies by employee count

1-10
37
11-50
17
51-200
5

Email recency for this list is measured across the whole United States list rather than for Washington, so it is reported there. Company counts and contact totals on this page are exact for Washington, over 59 companies.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among epa consulting firms, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source
The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
What qualifies
Companies headquartered in Washington, United States whose own description of what they do matches “epa consulting firms”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search
RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names epa consulting firms), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude
Companies whose own description does not clearly place them among epa consulting firms, and records with no verified work email. Companies headquartered outside Washington are excluded even when they keep an office there.
Match quality
In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
Ranking
Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification
Every listed company carries at least one verified work email, 245 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh
This page's figures were pulled from the company graph on September 28, 2026. Lists refresh periodically as the graph is re-checked.
Corrections
Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Frequently asked

What is RevenueBase Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names epa consulting firms, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many epa consulting firms are there based in Washington, United States?

RevenueBase identified 59 epa consulting firms headquartered in Washington, United States as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Peer Consultants, P.C, headquartered in Washington, tops this list with the largest team on record.

Which city in the United States has the most epa consulting firms?

Houston leads the United States with 90 headquartered companies, followed by New York (62) and Washington (59).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 245 verified decision-maker contacts tracked across these 59 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 28, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.